The six beach towns of Orange County, CA, offer lots of options. Huntington beach is good for swimming, surfing, and bodysurfing or head a bit further south to Newport Beach. Both places have loads by way of accommodations and kid-friendly activities. You might also look at Dana Point, surf's a little rougher here but a good jumping-off point for spring whale-watching cruises. If you're into the outdoors, you might look at camping at Doheny State Beach, too. Have fun!